Such a construction is known for example from DE 38 34 545 C2. The support housing disclosed there is comprised of a cylindrical base ring which is extended by three posts tapering in the axial direction and offset respectively about the periphery by 120.degree.. The end wall surfaces which lie between the posts serve to receive and secure three cusps [leaflets] which ensure the closing and opening of the heart valve. In the closed state, the cusp-shaped leaflets lie against each other at their free edges with the formation of an overlapping region. This construction as well as that of the construction described in DE 42 22 610 closely resembles the natural aortic valve in which the connection line between the cusp-shaped leaflet with the natural aorta root approximates the intersection of a cylinder with the aortic vessel. In this region the connection line closes the downstream side commissures in which the lines or the cusp-shaped leaflets lie. These commissures prevent the inversion of the cusp-shaped leaflets and serve in combination with the cusp-shape leaflet overlapping regions for bracing the opposing cusp-shaped leaflets.
To reduce the high stresses in the commissure regions, i.e. in the region of the posts, these must be formed so as to be flexible especially in their upper parts. There is however the danger that because of closing pressure differences excessive deformation will arise which can finally lead to creeping and as a consequence, to premature fatigue.